Engine



Dem. 12, 1944. vw. G. GERNANDT 2,364,629

ENGINE Filed Aug. 5, 1942 2 Sheets-Sheet l INVENTOR Dec. l2, 1944. W G', GERNANDT 2,364,629

ENGINE Filed Aug. 5, 1942 2 Sheets-Sheet 2- INVENTOR BWI/0 @er/742752Z.

W ATTORNEY Patented Dec. 2, 1944 ENGINE Waldo G. Gernandt, Detroit, Mich., assigner to Briggs Manufacturing Company, Detroit, Mich., a corporation of Michigan Application August 5, 1942, Serial No. 453,683

-22 Claims.

This invention relates to internalhcombustion engines and particularly to an engine .of the type having a rotatable valve in the cylinder vhead chambered to form a substantial portion of the combustion space. -In the present'embodiment of the invention the valve is of the conical or frusta-conical type and rotates within a similarly shaped cavity or bearing within the head. The valve is preferably, although not necessarily, of theltype which rotates continuously in one direction, and since the valve contains a 'large portion, and preferably nearly all,l of the com. bustion space when the piston is in its position of maximum compression, the valve is subjected to high temperatures during the power stroke of the piston; i

Adequate and uniform dissipation of heat from the valve in order to avoid overheating and hot spots and to maintain the valve at efdcient operating temperatures has presented serious -problems. Heretofore, the valve has been cored to provide an integral double wall construction so as to form a cooling chamber or Jacket surrounding the combustion chamber. chamber in preferred practice has been lilled, or nearly so, with metallic sodium which will melt under combustion chamber temperatures and provideA a satisfactory heat conducting medium.

Dimculties have been encountered, however, in vconnection with this practice.

On account of the expansion of the sodium within the cooling chamber not all of the chamber could with safety be initially iilled. Consequently, during operation a portion of the valve, which -required cooling, contained or was adjacent a dead air space. Thusruniform cooling .was impossible and adequate dissipation of 'heat was not obtained.

The' foregoing disadvantages have been overcome by virtue of the present invention, anjobject of which being to provide a construction by which all or any desired portion of the cooling chamber or jacket of the valve may be filled y with sodium or other heat dissipating medium and at the same time providing adequate space for expansion without danger of blow-outs4 or leakage of the sodium from the valve. w

A.- further object of the invention is to provide an internal combustion engine having a rotatable VAnother object is to provide an engine of the foregoing type'in which the' expansion chamber This coolingA for the' valve cooling Jacket is in the form lof a hollow member extending through the valve driving mechanism. 4

, Still another object of the invention is to pro- 5 vide an engine-of the foregoing kind in which the cooling jacket of the valve has an extension which projects beyond the valve into position to be cooled by air at a locality relatively remote from the valve andits combustion chamber.

l Other objects of this inventionwill appear in the following description and appended c1aims,.

reference being had to the accompanying drawings forming a part of this specification wherein like .reference characters designate correspondl5 ing parts in the several views.

as lines a-a of Fig. 2 looking in the direction oithe' arrows. Before explaining in detail the present invention it is to be' understood that the invention is not limited in its applicationv to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invenl tion is ycapable of other embodiments and of being practiced or carried out in various. ways.I

Also it is to be lunderstood that the phraseology or terminologyI employed herein Iis for the purpose of -description and -not of limitation.

In the drawings there is illustrated, by way of example, one embodiment of the invention as applied to an internal combustion engine of 'the spark ignition type designed particularlyfor the power plant of an aircraft. The invention may obviously be embodied in engines for other purposes, such as automotive, marine and industrial engines, and any number of cylinder unitsmay be employed in any given engine.

Referring to Fig. 1,-.the present engine comprises a plurality of cylinder units 22 extending from-a suitable crankcasanot shown.' Mounted to reciprocate within each cylinder is a piston 2l adapted to'be connected in the usual manner by a ,connecting rod 24. to a crankshaft I9.

In the present` engine the combustion chamber of the cylinder is formed principally within a rotor orV rotary member 2l, this member comprising a 'frusta-conical body arranged immediately above the piston 23 when the latter is at the top of its stroke. The rotor or rotary valve has an integral projecting cylindrical stem 25. The rotor fits within a similarly shaped substantially frustoconical cavity 21 in an upper cylinder head unit 28. In addition to the outer cylinder head member 28 there is provided an intermediate cylinder head member 25 which is in the form of a rotor mask or shield providing the throat opening from the cylinder into the combustionv chamber 34. The upper or outer end of the cylinder is formed with external threads which are engaged by internal threads on the cylindrical skirt portion of the member 28 as indicated at 30. The member 29 is provided with a cooling member 3| and is bolted to the cylinder head member 28.

Interposed between the upper and lower ends of the tapered wall of the valve or rotor 25 and the similarly tapered wall of the cylinder head cavity 21 are a pair of spaced rotatable thrust bearing rings 32 formed of suitable material, such as bronze or lead bronze alloy. It will be noted that the rotor is formed with annularly extend. ing recesses to receive the frusto-conical rings 32, these rings providing free floating bearings between the rotor and the'cylinder head 28. The

construction in this respect is preferably similar to that shown and described in my copending application Serial No. 441,474.

The rotor mask or shield 29 terminates centrally in a projecting annular flangev which forms the throat opening l33 into the combustion cham ber 34 of therotor member or rotary valve 25. The valve has a port communicating directly with vthe throat opening 33 and of the same area. The

valve also has a port opening 35 in a side wall thereof, located between the bearing rings 32, and

ing chamber or cavity 55 which preferably extends entirely around the combustion chamber 34. This cooling chamber is separated from the combustion chamber and the wall 21 of the bearing cavity in the cylinder head by relatively thin walls, and except for the opening 'through the upper end of the stem 26 the cooling chamber is entirely enclosed within the rotor body. A Suitable cooling or heat conducting medium is placed within the cavity 55 and in the present instance this heat conducting or dissipating medium is in the form of metallic sodium. The stem 25 is provided with an internally threaded counterbore adjacent its outer end and ilttingwithin this counterbore and attached to the threads thereof is a hollow tubular plug member 51 which forms an expansion chamber for the cooling medium within the valve cavity 55. The member cooperating with longitudinal splines on a coupling member 40 which in turn is in mesh by means of splines or gear teeth 4I with a driving gear 42. This' gear has a cylindrical hub portion 42a adapted to rotate within a fixed bearing bushing 42 secured within a recess in the cylinder .headl The parts are held in position by means of a clamping nut 44 which engages a resilient Vor yieldable washer-45 interposed between the nut and the gear 42.

The driving. geary 42 for each rotor 25 meshes with a gear 45 secured tov alongitudinal shaft 41 rotatable within 4suitable bearings 4I carried by the cylinder head. It will beunderstood that each cylinder of the engine is provided with a rotor .or rotary valve 25 and each valve is driven by a gear42 meshing with a gear 45 on the shaftv 41, this shaft being common to all of the cylinders of the engine. Attachedto one end of the shaft 1 is a'gear 40 meshing with a gear 50 secured to the upper end of a tower shaft 5|. shaft is revoluble within suitable bearings and extends through a housing .52. A gear 5I is se cured to the lower end of the tower shaft and meshes with a gear v54 attached to the .crankshaft IB.

The valve or rotor 25 is cored to provide a e001-,

This' 51 has exterior threads 55 cooperating with the internal threads of the stem 25. It will be seen that the clamping nut 44 has internal threads cooperating with` the external threads of the member 51 so that the clamping nut is thus attached to the stem'25 and drawn 'down tightly against the spring washer 45 through the medium of the tubular member 51 which in eil'ect forms the coupling medium between the nut 44 and the valve stem 25. The member 51 extends into the air space above the gear 42 and may be of any suitable height Providing there is clearance between the member 51and the housing or cover 59 for the valve drive mechanism. f

In practice the metallic sodium 55 normally does not till the chamber 5l and the chamber within the tubular member 51 since suitable space is preferably allowed for expansion when the sodium becomes heated during operation of the engine. The capacity of the expansion chamber within the member 51 is such, however, that the metallic sodium may extend, when the valve is cold, substantially to the line or, in other words, to the top of the valve stem 25. 'I'his leaves an expansion space 5I within the member 51; If desired, this member may be provided with external cooling fins 82. The over-all diameter of the finned portion of the member 51 is somewhat less'than the threaded portion 55 so as to permit removal of the clamping nut 44 and also to permitthe valve to be removedthrough the bottom of the cylinder head cavity 21, when dis-v assembling the parts, without necessitating re-f moval of the tubular plug member 51.

From the foregoing it will be seen that the metallic sodium or other suitable cooling medium will extend substantially entirely around the combustion chamber 34 in intimate contact with both walls of the cavity and'may also extend well up into the hollow valve stem 20. The space 5I -permits expansion of the 'cooling medium during operation and all air trapped and compressed by the sodium will be in the outer end of the tubular member l1 where the heat may more readily be dissipated therefrom. The fins I2 will assist in conducting heat from the sodium andl to the trapped air within the expansion space 5I.

I claim:

1. In an internal combustion engine having a cylinder, a rotatable valve having a combustion chamber communicating with said cylinder and a cooling chamber' adjacent said combustion chamber, means 'connected to one end of said valve for driving .the same, andV a removable member for closing said cooling chamber and having therein a chamber extending exteriorly oisaid valve and communicating with said cooling chamber.

2. In an internal combustion engine havingV a cylinder, a rotatable-valve formed with a c'oxnbustion chamber communicatingfwith said cylinder' and having a cooling cavity within the said chamber, said valve having a hollow stem, a geardrivingly connected to the stem, and a hollow member extending from s aid stem through the gear and communicating with said cavity.

3. In an internal combusion engine having a cylinder, a rotatable valve formed'with a combustion chamber communicating with said cylinder and having a cooling cavity within the lwalls thereof extending at least in part around 'said'chamben said valve having a hollow stem,

a gear drivingly connected to the stem, a hollow member extending from said stem through the gear and communicating with said cavity, and

l-means secured to said member for holding said gearin position.

Ameans and forming a continuation of said coolwalls thereof extending at least in part around in g chamber. 1

9. In-an internal combustion engine having a cylinder, a rotatable generally frusto-conical valve having a combustion space and formed with a cooling chamber within the walls thereof embracing said space, said valve having s. hollow stem, gear means connected to the stem for ro- 4. In an internal combustion engine having a cylinder, a rotatable valve formed with a cambustion chamber communicating 'ith said cylinder and having a cooling cavity within the walls thereof extending at least in part around said chamber; said valve having a' hollow stem,v -a gear connected to the stem to permit relative axial movement of the gear and stem, a. hollow member formingan extension of said cavity and extending through the gear, and means connectedf to said member for yieldingly holding said gear in position.

5. In an internal combustion engine having a cylinder, a rotatable valve formed with a combustion chamber communicating with said cylinder and having a cooling cavity within the walls thereof extending at least in part around said chamber, said valve having a hollow stem, a gear connected to the stem to permit relative tating'the valve, and an extension-of said-stem projecting through'said gear means and forming a continuation of said cooling chamber.

' 10.*In aninternal combustion engine having a cylinder, a rotatable valve having a combustion space and -formed with a cooling chamber within the walls thereof embracing said space, said valve having a hollow stem,l gear means connected to the stem for rotating the valve, and an extension of said stem detachably connected thereto and projecting through said gear means and forming a continuation of said cooling chamber.

11. In an internal combustion engine having a cylinder, a rotatable valve having a combustion space and formed with a cooling chamber within the walls thereof embracing said space, said valve having a hollow stem, gear means connected toA the stem for rotating the valve, an extension of said stem projecting through said gear means and forming an continuation of said coolingchamber,

and a clamping element detachably connected to said extensionand coacting with said gear means.

' l2. In an internal combustion engine, a rotat- ,l able valve having tapering side walls converging axial movement of the 'gear and stem, a-hollow member forming an extension of said cavity and extending'through the gear, means for detachably connecting said member to the stem, an'd means connected to said member for yieldingly holdingsaid gear in position.

6. In an internal combustion engine having a cylinder, a rotatable-valve formed with a combustion ychamber communicating with said cyl'- Ainder and having a cooling cavity within lthe in one direction and having an axially projecting hollow stem connected thereto, said valve having a combustion space therein and also a cooling cavity within the walls thereof embracing said chamber, said cavity extending through said stem, and a hollow plug member closing lsaid cavity and detachably connected to the stem, said plug meniber forming a continuation of the cavity beyond the end of the stem.

13. In. an internal combustion engine, a rotat-v able valve having tapering side walls converging in one direction to provide a relatively narrow portion, said valve having a combustion space therein and also a cooling cavity within thewalls thereof embracing said chamber, and a hollow' plug member closing said cavity and detachably walls Vthereof extending at least in part around said chamber, said valve, having a hollow stem,

a gear drivingly connected to the stem, and a cylinder, a rotatable valve having a combustion space and formed with a cooling 'chamber within thefwalls thereof embracing `said space, said valve having a hollow stem, gear means connected to the stern for rotating the valve, and an exten-y sion of said stem projecting through said gear connected to the valve, said plug member forming a continuation of the cavity beyond the end of said narrow portion and having walls positioned for heat exchange relatively remote from the valve combustion space.

14. In an internal combustion engine having a cylinder, a rotatable valve having a combustion space and formed with a. cooling chamber within. the walls thereof embracing' said space, gear means connected to the valve for rotating the same, and an extension of said valve projecting through said gear means and forming a. continuation of said cooling chamber, said extension hav'- ving a finned portion positioned for heat exchange relatively remote from the valve combustion space'. 15. In an internal combustion engine having a cylinder, a rotatable valve having a combustion Y space and formed with a cooling chamber within the walls thereof embracing said space, said valve having a hollow stem, means embracing said stem for holding the valve in operative position, and U an extension of said stem projecting through saldi means and forming a continuation of said cooling chamber, said extension having an outside diameter not exceeding that of the stem to permit said means to be withdrawn from the stem and its extension axially 'of the valve.

16. In an-internal combustion engine, a rotatable valve having tapering side walls converging in one direction and having an axially projecting hollow stem connected thereto, said valve having a combustion space therein and also a cooling cavity within the walls thereof embracing said chamber, said cavity extending through said stem, a hollow extension of said stem forming a continuation oi.' the cavity beyond the end of the stem, and driving means for the valve embracing the stem, said extension having an outside diameter not exceeding that of the stem to permit installation or removal' of the valve and said extenl sion as a unit relative to said driving means.

and detachably connected to the stem, said plug member forming a continuation of the cavity beyond the end ofthe stem, said plug member having an outside diameter not exceeding that of the stem, and a clamping nut threadedly connected to said plug member.

18. In an internal combustion engine having a l cylinder, a rotatable valve having a combustion space communicating with the cylinder and a cooling chamber adjacent said combustion space, and ayremovable member for closing said chamber and having therein a chamber forming a continuation of said\cooling chamber.

19. In an internal combustion engine having a cylinder, a rotatable valve having-a' combustion space communicating with the cylinder and a cooling chamber adjacent said combustion space, and a removable member ior closing said chamber and having therein a chamber forming an extension of said cooling chamber beyond the latter.

20. In an internal combustion engine having a space communicating with the cylinder and a cooling chamber adjacent said combustion space, means for driving\the valve, and a closure member detachably connected to the valve for closing said chamber and having a chamber forming an extension of said cooling chamber.

21. In an internal combustion engine having a cylinder, a rotatable valve lformed with a combustion chamber communicating with said cylinder and having 'a cooling cavity within the walls thereof extending at least in part around said chamber, said valve having a hollow stem, and a hollow member extending from said stein having a chamber forming an extension oi said cooling cavity.

22. A rotatable valve for an engine comprising a body formed with a combustion space and a cooling chamber associated therewith, a closure 'member detachably connected to the body for closing said chamber and having a chamber Iorming an extension of lsaid cooling chamber.

G. 'GERNANDT 

